Incontinence in men relates to a reduction or loss in urethral sphincter function. For example, the prostatic urethra is at times removed or altered during prostate surgery, which can lead to a reduced ability in the urethra to coaptate. Incontinence in women relates to a loss in support of the female urethra, for example as one or more of the pelvic organs prolapse, which allows urine to leak out of the urethra. Pelvic organ prolapse is a disorder related to the dropping down (prolapse) of the bladder, rectum, or uterus caused by weakness or injury to ligaments, connective tissue, or muscles of the pelvis.
A hernia is a protrusion of a body organ through the wall of the body cavity.
Meshes are at times implanted into the body to support the urethra, or to support prolapsed organs, or to reinforce the wall of the body cavity. Meshes include knit meshes and woven meshes.
FIG. 1 is a top view of a prior art knit mesh 10 including a filament 12 knit on a path to form a chain of loops 14, where each loop 16 in the chain of loops 14 is suspended by a neighboring loop 18. In this manner, the loops 14 are secured as they are knit by passing a newly formed loop (e.g., loop 16) through a previously formed loop (e.g., loop 18). The chain of loops that run left-to-right in FIG. 1 are referred to as a wale W. The path that the filament 12 follows is referred to as a course C. The loops 14, 16, 18 of the prior art knit mesh 10 will unravel if pulled with a sufficient force, or if one of the loops is broken or severed.
A woven mesh is not a knit mesh. A woven mesh is formed by threads that run parallel in a lengthwise direction (warp threads) and cross with a separate set of parallel threads placed in a crosswise direction (weft threads). The meandering course C that forms the loops 14, 16, 18 of the prior art knit mesh 10 provide the knit mesh 10 with greater elasticity (e.g., stretchiness) over the woven mesh since the loops move within each other. Some surgeons prefer knit mesh materials over woven mesh materials for body implantation around the generally curved body organs.
Knitted mesh materials are effective for use as body implantable fabrics. However, these knit mesh materials are susceptible to unraveling or tearing when pulled on during placement in the body, which can lead to undesirable tearing of the knit mesh.